[DoDEA Science]

DRAFT

Astro Tides

Astronomy

Grade Level	10-12
Standards	Astronomy Content
		Students will describe physical characteristics of the moon and quantitatively evaluate the moon's effect on the Earth

Objectives	Students will be able to determine orbital and physical characteristics of the moon (i.e.. mass, diameter, and distance from Earth). Students will be able to explain how the moon affects the Earth's tides and the impact of these tides on the Earth's economy.
Materials and Activities
Materials
Engage	A. Students will be asked to answer the following questions: 1. What causes the tides? 2. Which is greater, the gravitational force between Earth and Sun or Earth and Moon? B. Students will be given the following formula to calculate the gravitational forces: F e-s= G Me Ms / d2e-s = Fe-m= GMeMm / d2e-m = ( The gravitational force of the Sun is greater)
Explore	Students will now calculate the differential force that is applied to the earth by the moon and the sun. To do this they will need the following formula: Force of Earth-Sun near side: F = GMeMs (de-s - re)2 Force of Earth-Sun far side: F= GMe*Ms (de-s + re)2 de-s Students will use the textbook on Appendix 2A to look for the basic constants, for the above formulas. The students will use a spreadsheet to calculate the forces and by graphing compare and contrast the results.
Explain	The students will be able to explain their findings and how the differential forces cause tides.
Elaborate	Students using the internet and other sources will do an oral report on tides as sources of energy. Students can also do internet research to find out how tidal forces affect characteristics of Jupiter's moons.
Evaluation	Students will be evaluated on the spreadsheets and graphs. Students will evaluate each other's oral reports.
Homework	Students will be able to look for links related with tides.

Teacher notes/reminders

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